What I learned from my ATX transaxle

My torque converter has planetary gears inside it and something broke inside resulting in a bunch of small metal fragments which looked like gear teeth all inside the torque converter. The engine was shaking at idle and less at driving speeds. I had to take the transaxle apart to find out if any of those metal particles made their way in. It turned out none of them did which surprised me. My transaxle is original and has 130K miles on it. So this is what I learned about the whole thing.

First, there is a free pdf book about 96 pages on the internet about the ATX transaxle for our 1st gen escorts. Before I discovered the pdf I bought haynes ATX transmission book which has lots of pictures and step by step assembly/disassembly steps. The number for the haynes book is# 10355 and I bought my new for $20 on ebay. I don't have the link to the free pdf but if you search for "ford ATX transaxle" it will popup in first few search results.

Taking the transaxle apart is easy except for the planetary gear set which was stuck and I had to use three jaw puller and a sliding hammer to pull it out. There are notches in the face of the gear set for the jaw puller to fit into. Neither book mentions this, they say simply "remove the gear set". As far as tools go, you need flat screwdrivers (small and larger ones) for prying out the various metal rings securing parts together. You'll also need some long nosed snap ring pliers to remove snap rings from the clutch packs.

About the valve body. Our escort transaxle was designed to be easily serviced while in the car. So there is a valve body cover you need to remove and then you'll see the aluminium valve body with all those ant like passageways. In that hunk of metal there are 16 variously sized valves, none of which have any rubber o-rings or any rubber inside it. The valves are precision fit for the bores in the valve body, thus if you damage a valve you have to get a new valve body with its valves. You can't take one from one car and put it into your car unless you have a machine shop and can make a new valve yourself but that is beyond this post. So here's what I ran into. The pressure regulator valve had a small burr on the inside which I didn't know so when I removed the valve, it got scratched up. One long and shallow scratch. Too shallow to fill with jb weld. I just removed all the valves and then snapped pictures of the valves so I knew how to put it back together. The pfd book has a diagram of all the valves which I used on most valves, one or two I had to reference back to my pictures. I dipped the valves in automatic transmission fluid when I installed them back. I put back the pressure regulator valve in without any fix and will see if doesn't leak. You can measure oil pressure and see if you're getting some. There is a screw next to the valve body and accessible from outside that you measure pressure with.

The valve body was the most complex thing I've cleaned and assembled on the ATX. There was a dark film on the inside and outside of the valve body. I think it could be microscopic metal particles the same found in the ATF oil pan. No larger metal shavings found. When you're working with the valve body you have to make sure everything is clean inside, no hair or lint, etc. Once done you should dip the valve body into ATF fluid before bolting it into the ATX. Also, make sure all the valves slide freely by using a screwdriver to push them open. They should snap close by spring pressure. Don't use magnetized screwdriver to pull out the valves out of the body because it will magnetize the metal valves and metal particles will be attracted to the valve and may cause it to not slide back again. I used a small popstickle stick to shove a spring inside the bore and then put the retaining clip down onto the stick and then removed the stick. You're welcome for that tip It's probably best to simple clean the valve body from outside without removing the valves if you know you don't have metal shavings inside the ATX. I didn't so I had to remove the valves and check their insides, etc. My ATX had six check valves, one too many for my style of torque converter according to the pdf book. There are three torque converters ie. planetary gear set(mine), CLC and FLC. My suppose to have 5 check valves, CLC six and FLC seven. You can't exchange the torque converters willy nilly. I will leave six check valves in mine because I know it works, not sure what the pdf book talks about.

Clutch packs. There are three clutch packs. They are held in by a large metal snap ring. The books use special spring compressors to compress the clutches so you can remove the retaining snap ring. I was able to use four smaller C-clamps on the direct clutch. I used a empty roll of painter's tape, put that onto the top of the spring assembly and then used the c-clamps to push that roll down. This way there was equal pressure applied all around the circumference of the spring assembly. If you just use the c-clamps without that paper roll then you will bend the spring assembly plate in four places and then have to straighten it out. That happened to me when I removed the intermediary clutch spring assembly. Best thing to do is to find a transmission shop and ask them to compress those clutch packs for you. Just take those with you and you don't need the ATX case at all. When I install the clutch packs I ask for help from the shop.

So what was the state of the ATX after 130K miles? All the gears, bearings and bushings showed minimal wear and acceptable for another 100K miles. The differential was no worn out and if you were to take it apart you need special tools and drill out the rivets and add bolts afterwards. So unless the gears are gone I wouldn't disassemble it. To remove one last gear from the ATX you'll need 12 point 32mm socket and it was hard to remove because ford used really strong yellow locktite on the nut. Use the socket and don't use anything else otherwise you'll round off the nut. I was smart and I stopped before doing damage, went to autozone and for ten bucks got the socket.

All of the friction plates were good except for one clutch pack that showed divots in the plates. I'm going to replace all the friction plates. The steel plates look like new, no deformations. I used flat glass to check each one for warping. The surface was shiny and I think I'll scuff it up lightly with red scotch brite pad to put some crosshatch pattern on it so it would grab the friction plates better. The band was mostly good and only on one spot was the friction surface worn by removal of the top coat. Still usable but will buy a new one. Will have to see if the new one will be same depth as that might change the specs and new servo pin will have to be put in, maybe.

So my ATX will need new friction plates and all new seals along with paper gaskets for the pump and valve body. Also new gaskets for oil and valve body pan, new oil filter and two new seals for the differential where the CV axles go into. I removed the servo from the ATX using a crow bar hooked to the small screw and then pushed the bar in which compressed the servo into the ATX case and with my free hand used small screwdriver to pry the snap ring out. Then I went on ebay and bought a special tool otherwise two people have to put the snap ring back in place. The tool cost me $20.

For closing, the ATX worked great before I took it apart and you might not be so lucky with yours but it's easy to take apart and put back together. There are no electronics except for the neutral safety switch and that's I kept attached to the ATX case. I also kept the old TV shaft seals because if they leak I can easily replace them with the ATX in the car. The last seal I will maybe replace is the one that's attached to the ATX case, the one that the torque converter snaps into. If I have to take down the gear with special puller to get the seal out I will instead leave it in, if not then I will take it out. That puller looks expensive. That seal looks like it will easily last another 100k miles.

Could I have not replaced anything and to just clean the insides and be ok for another 100K miles? Maybe, but I feel more confident with new seals and new friction plates, etc. The friction plates seems to not last beyond 150-200K miles and mine were showing some deep pitting along the surface. Hopefully someone will find this post helpful and I wrote it to let you know that the ATX is easy to take apart and service so no worries. I've already rebuilt the engine and now the ATX. As long as those two are done then the car will last for a very long time and I think we all want that.

Here's a picture of my ATX on my kitchen table. I don't have a garage but I did use harbor freight 2 ton lift to raise it onto a small table, take it apart piece by piece and store the pieces on my kitchen table. I cleaned all the parts with walmart's carb and brake cleaners, $2 per can, used couple of cans. Took three days to take apart at leisurely pace.

I remembered something interesting about the governor weights. The governor uses four weights, two on each side that spin as the governor spins. The weights are pushed outward and then they move a valve inside the governor that modulates the oil pressure. There are two large weights, 180 degree opposite each other and then in each one is a hinged smaller weight. On one side the weights were locked together by a spring. The spring pushed the small weight onto the larger weight. On the other side, there was no spring and the small weight can move on its own. The spring is hard to remove and that leads me to believe that during disassembly it wasn't lost but simply not included by design. It's also possible that I lost the spring and by design on this ATX both small weights should be locked to the larger weights and I won't know for sure until I drive the car which will be several weeks from now.

Maybe someone can chime in and shed some light on this matter.

Good write up. I'll add that if you have a drill press, it's a great tool to compress clutch packs. Just find a suitable diameter something to put on the clutches, and bear down with the drill chuck. When it's compressed properly, lock the quill.
Edit: Don't turn on the drill press. Unplug it before starting.

A scratch, even a deep one, on a valve will not cause problems if it is simply polished a bit so that there are no protruding ridges. A very very tiny amount of ATF will leak past, not enough to matter.

That's a good idea about using the drill press to compress the springs. I can't tell you how many times I was in despair and then remembered this trick, even now I lightly scuffed the scratchs so the valve would slide easy and not hang up in the bore. I feel better now after what you just said about it not being a big problem. I have the ATX transaxle with the governor and weights. The F-4EAT was a 4-speed, electronically controlled automatic transmission developed by Mazda and JATCO starting in 1990. It was also later produced by Ford Motor Company from 1991 to 2003, to replace the aging, 3-speed/hydraulic controlled ATX.